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R Weberling

Publications and source records attributed to R Weberling.

6 recordsLinked to original sources
PubMed1990

[Minimum resolution at a given dose for quality assurance of x-ray pictures].

The Federal German Board of Physicians ("Bundesärztekammer") has recently issued guide principles for quality assurance in x-ray diagnosis. These include the basic measurements defining important image details, sensitivity of screen-film combinations and exposure times. The conditions required for meeting the guide principles were tested, using low contrast grids for simulating tissues. Practical consequences from these measurements for radiographic techniques and for the use of test grids in quality assurance are detailed.

Germany, West↗
PubMed1989

[Documentation of medical images using a laser camera].

For today's and tomorrow's high developed imaging systems CT, MR, DSA, NM, US, DR we need equally highly developed recording equipment to produce high-grade quality "hard copies" at the end of the image transfer chain. For this reason we present a new laser image recording technique with Laser Imager and its operational principle. The Video Imagers (multiformat cameras) used until now are no longer up to date due to their disadvantages for imaging documentation of high-resolution imaging systems. The direct exposure of a single-emulsion-silver-halogenide transparency film with laser light, produces low-noise distortion-free and homogeneous documentation images. The size of the matrix of 4000 x 5000 pixel and 12 bit image depth guarantees the use of the Laser Imager also for future imaging systems with a higher size matrix than is now usual. The modulated accessories such as Multi-Modality Unit (MMU) and Multi-Console Laser Switch (MCLS) guarantees a flexible and more economic use of the Laser Imager.

Copying Processes↗
PubMed1985

[Results of a study on roentgen film processing in automatic film-developing systems].

100 X-ray film developing machines in 72 institutes were tested for accuracy of reproduction of the film developing systems by means of sensitometric methods for a period of 9 months. If we assume the sensitivity index to be D = 1.0 with a maximum variation of +/- 0.2, one-third of the machines in this test are not within the standard range. Hence, to ensure maximum utilisation of the sensitivity of the film processing systems, it will be necessary to keep a close check on the development process.

Germany, West↗
PubMed1979

[Examinations of rare-earth film-screen-systems for image detectors in mammography (author's transl)].

Intensifying screens based on Gd2 O2 S : Tb were analysed for x-ray exposure reduction and resolution using in mammorgraphy. The contrast of these screens coupled with a single emulsion film was tested and the density dominante was determined. A resolution grid on this density exposured shows the detail resolution and judge the quality profile of these new film-screen-combinations. To all factors was compared a non-screen industrial film for long time processing. The application of Gadolinium intensifying screens in mammography allowed an exposure reduction of 75% at the same image quality like a nonscreen industrial film.

Female↗
PubMed1978

[New intensifying screens in clinical radiology III: Screen-film combinations in mammography (author's transl)].

An industrial film was compared with four commercially available screen-film combinations with respect to dose, definition and signal to noise ratio. The demanded minimum resolving power requires definition of an object of 100 micrometer size. However, the defined minimum object sizes are approx. 180 micrometer with close-distance projection and approx. 240 micrometer with greater distance. In this study, therefore, the signal to noise ratios were measured at defined object sizes of 5 lp/mm and 2 lp/mm. The screen-film combinations have approximately the same values as the industrial film for a size of 250 micrometer (2 lp/mm) or are definitely higher. The signal to noise ratio of the Alpha M combination is superior by 50%, although the sensitivity of the combination is 4 to 6 times greater. The signal to noise ratio of the MinR system in 25% higher than that of the industrial film, the required dose being lower by a factor of 8. This results in skin doses of 0.7 rads instead of 6 rads with tissue layers of 4.8 cm thickness.

Female↗